1. Field of the Invention
Embodiments of the present inventive concept relate to a fusing device to fix an image on a print medium and an image forming device including the fusing device.
2. Description of the Related Art
An image forming device prints an image on a print medium and includes printers, copiers, facsimiles, multifunction copiers in which functions thereof are integrated and the like.
An image forming device utilizing electrophotography irradiates light to a photosensitive material charged with a predetermined voltage to form an electrostatic latent image on the surface of the photosensitive material and then supplies a toner to the electrostatic latent image to form a visible image. The visible image formed on the photosensitive material is directly transferred to a print medium or is indirectly transferred to the print medium through an intermediate transfer unit, and the visible image transferred to the print medium is fixed on the print medium while passing through the fusing device.
In general, a fusing device includes a heater including a heat source, a roller, a belt or the like and a pressurization unit contacting the heater and thus forming a fusing nip. When the toner image-transferred print medium is inserted between the heater and the pressurization unit, a toner image is fixed on the print medium through heat transmitted from the heater and a pressure applied to the fusing nip.
Gloss and gloss uniformity of the toner image-fixed print medium are major factors determining qualities of image printed to the print medium. In order to obtain superior gloss and gloss uniformity, application of high fusing pressure near the fusing nip formed between the heater and the pressurization unit, and width uniformity of the fusing nip are required.